Fifth wheel



F. H. KAYLER Dec. 9,1952

FIFTH WHEEL 5 Sheets-Sheet l Filed July 16, 1949 Q Nm.

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F. H. KAYLER Dec. 9, 1952 FIFTH WHEEL 3 Sheets-Sheet 2 Filed July 16, 1949 NNI Dec. 9, 1952 F H, KAYLER 2,621,056

FIFTH WHEEL Filed July 1.6, 1949 3 Sheets-Sheet 5 47 ,222 /W// f/////// 2. .Z22 22 f5 Y /f 70 el@ zo a? .Q-I-'lum IN V EN TOR.

Patented Dec. 9, 1952 ITED :S TT'ES AA'fE-N'i OFFICE FIFTH WHEEL Frank H. Kayler, Alliance, Avliio, -assignor :to

American .'Stcel '.Foundries, Chicago, Ill., a corporation. of .N ew Jersey Application Julyli, 1949, .Serial 'No.`1ll'5,080

-2 Claims. 1

This invention relates 'to a fth wheel incorporating a coupling mechanism of the type 'shown and described in Patent No. 2,015,313, issued in the United States Patent'Ofce on September 24, 1935, to'Edmund P. Kinne, 'and more particularly to an improvement in 'thelo'cking 'means for said mechanism.

A 'general object of the invention is to .provide lock means 'for such a coupler which will have a rapid positive locking action and which, 'when 'in locking 'position with the coupler, is positively prevented 'from moving vto unlocking position such as will accommodate uncouplingiof the coupier.

'The invention ,contemplates 'the provision of actuating means in the form of springs for the locking means arranged 'in an emcient manner to urge the lock into locking engagement with the coupler when the latter is in coupling position.

A further object of the invention is the provision of locking means which may be incorporated in couplers of the type described and presently in use.

These and other objects of `the invention will become more apparent from the spec'ication yand the drawings, wherein:

Figure 1 lis a perspective -view of .a lilith wheel assembly incorporating .the invention, the fifth wheel being shown in .phantom lines to rmore .clearly illustrate .the coupling andloc'king mechamsm;

Figures 2 to sare vertical sectional views taken substantially on the .line A-A of Figure 1, Figure 2 illustrating the lmechanism `in locked or coupling position, Figure 3 .showing the mechanism in lockset position for uncoupling, and Figure 4 showing .the mechanism in uncouplecl position;

Figure 5 is a vertical sectional view taken substantially on the line B--B of Figure 1 with the mechanism in lockset vor uncoupling position as in Figure 3; yand Figure 6 is a -top plan view of thelocking member.

'Figures 7 to 9 illustrate a modification of the invention for use with heavy duty fth wheels, Figures 7 and 'S being views comparable to 'Figures 2 and 5., respectively, .and Figure 9 being atop plan View of the modified 'form of locking member.

Describing the invention in detail, the iifth wheel, generally designated 2, comprises 5a top plate d. forked towards its .rear extremity to provide spaced legs 6 t den-ning a slot 8 therebetween leading into a throat l0 at the center of the plate. The slot accommodates entry Vof a (Cl. 28th-33.05)

2 king pin Il on Ia trailer plate i3, (Figure '2) into the throat for coupling with a coupler mechanism, generally designated '|2, as will be readily understood by 'those skilled inthe art.

The plate ll is pivotally supported at each side thereof on 'a bracket 'lli adapted 'to 'be Vmounted on Ya tractor 'frame structure indicated `at I6, I6.

The coupler mechanism l2 is 'operable within a housing 'I8 which .is formed integral with the top plate -t,said mechanism comprising aforward member orjaw 2i) hingedly or pivotally connected as at 22,22 to a rear member or 'jaw 25'.

The .coupler member 2Q .comprises a .central body portion 2t provided with laterally extending wall portions 28 and '39 `from whichproject ledges 32 and sa. slidably supporting the jaw member 2Q on ilanges .36 and 38, respectively (Figures 2 .to 5), of the housing I8.

Similarly, the coupler member .24 'has a body portion til with integral, laterally extending wall portions E2 and mi `provided with 4ledges 4t Yand 28 slidably supported on the flanges 33 and '38 of the housing.

The body portions .26 and lli) .are formed with recesses '5G and 52, respectively, .adapted in vthe closed or coupling position of the coupler members 28 and 2li to define .a socket, as shown in Figures .1 to 1, for confining the king .pi-n therein, the recesses being contoured to .afford locking engagement between the .pin and the coupler members, as will .be .readily understood by those skilled in the art.

In the coupling position of the mechanism .as shown in Figures l and 2, .forward translatory movement of .the coupler members 2i] and 24 within the housing is .restricted by a block of resilient material '511, such as rubber, pocketed in thehousing between the .front face 56 of member '2,9 and a front wall 58 of the housing and Aconfined between the top plate 4 and the side walls and bottom wall 60 of the housing.

Rearward translatory movement .of the members S28 Vand 2li within the housing inthe coupling position of the mechanism is prevented by a locking unit, generally `designated .62., and comprising spaced legs or locking `portions 64 .and -66 in engagement at their forwardends as at 68 vand 1d, respectively, with complementary faces -on the rear sides of wal-l portions 44 and .42 of the rea-r coupler member As readily seen in Figure 2, the engaging faces on legs -64 and 65 4and portions fifi and i352 are deiined from the axis of rota-tion of unit .S2 `and are curved vertically.

rhe legs et Vand '5S are integrally formed at their rear ends with depending legs l2 and :14,

respectively, which are integrally united at their lower ends by a crosspiece or bar 16. The locking unit is pivoted on pins T8 and 39 extending through openings formed at the juncture of legs 64, 'l2 and 66, 14, the pins being suitably secured to brackets 82 and 84 formed on plate 4'.

rEhe locking unit 62 is biased or rotated to locking position with the rear coupler member by a plurality of springs 88 and 88, spring 86 being of tension type and having one end hooked around a lug 99 formed on the lower end of the external side of leg 12 of the locking unit. The other end of the spring is hooked to a depending lug 92 on the plate 4 and disposed rearwardly of the locking unit 62.

The other spring 88 is of compression type and at its upper end seats as at 94 against the underside of plate 4 and is positioned thereon by a boss 9S integrally formed on the plate 4. The lower end of the spring 88 extends into a vertical pocket 8S formed in the leg 68 intermediate the ends thereof. The pocket 58 is open through the top of leg 65 and at the bottom thereof is provided with a spring seat |88 affording a seat for the lower end of spring 86. It will be noted that the sides |82 and |84 of the pocket forwardly and rearwardly of the spring S8 diverge upwardly to accommodate rotation of unit 62 without binding or abrading leg E36 against the spring 88, as will be seen from a comparison of Figures 2 to 4.

It will be noted that the action of the springs 85 and 88 in the locked position of the unit 62 prevents the legs 64 and 56 from creeping upwardly out of engagement with the faces on the rear sides of the wall portions 42 and 44 of the rear coupler member 24. Furthermore, failure of either spring or removal of spring 86 by vandals will not affect the operation of the other spring. In addition, the locking means herein described may be readily incorporated in existing coupler assemblies employing the arrangement set forth in the before-mentioned patent to provide a rapid, positive locking action.

The unit 62, including the legs or members 64 and 66, is moved or rotated on the transverse pins 18 and 88 to unlocking or lockset position with the forward ends of said members disposed above out of locking engagement with the rear surfaces of the walls 42 and 44 of the rear jaw 24 by means of a cam member or dog |86 mounted on a shaft |88 supported for rotation on a bearing provided in a bracket IIB (Figure 2) formed on the plate 4.

The cam member is disposed beneath the leg S4 of the locking unit 62 and is provided on its top side, forwardly of its rotational axis I2 (Figure with an arcuate cam surface I I4 adapted to engage a cam surface cn the underside of a lug I I 6 disposed on the outer side of leg 64 intermediate the ends thereof.

The cam member is rotated in a counterclockwise direction (Figures 1 and 5) by an operating assembly, generally designated ||8, to raise the legs 84 and 65 to unlocking position as shown in Figures 3 to 5 whereupon spring 8S is expanded and spring 88 is compressed. The operating assembly will not be described inasmuch as it forms no part of the present invention and is adequately explained in the before-mentioned patent.

The unit 62 is maintained in locked position with the legs E4 and 58 thereof raised above the wall portions of the rear coupler member 24 by the forward end of the cam engaging behind a shoulder |28 on the underside of lug IIS intermediate the ends thereof.

In the lockset position of the locking means, as seen in Figures 3 and 5, the front and rear coupler members are permitted rearward movement within the housing. Rearward movement of the members 20 and 24 is effected by moving the tractor (not shown) on which the fifth wheel assembly is mounted, in a forward direction. The king pin which is disposed in the socket, causes the members 28 and 24 to slide rearwardly on their ledges along the flanges 36 and 38 of the housing.

It will be noted that the top sides of wall portions 42 and 44 of member 24 are provided with curved surfaces |22 and |24, respectively, adapted to engage the undersides of the legs 66 and 64, respectively, when members 2D and 24 are moved rearwardly whereby the legs are raised to a position disengaging the cam from the shoulder |20 whereupon the cam is caused to rotate in a clockwise direction (Figures 1 and 5) by the operating means I|8.

It will be noted that the anges 36 and 38 of the housing are curved downwardly rearwardly at |26 and |28, respectively, and that the undersurfaces of the flanges 46 and 48 are curved downwardly at |30 and |32 from the forward ends of said ledges to points intermediate the ends of said ledges whereby, as said ledges ride on the curved surfaces |26 and |28 of the housing flanges, the rear member 24 is caused to rotate downwardly at the pivot points 22, 22, thus opening the king pin confining socket and permitting exit of the king pin from the throat |Il of the plate through the slot 3, effecting uncoupling of the tractor and trailer.

It will be seen from a consideration of Figure 4 that in the uncoupling position of the coupler, the legs 64 and B6 abut against the rear sides of the walls 28 and 30 of the front jaw 2U, preventing the coupler from falling out of the housing.

To couple, the king pin is entered through the slot 8 into the throat |IJ whereupon it engages the forward jaw 20 within recess 50. The front member is moved forwardly into the housing, pulling the rear member which, riding on its faces |38 and |32 against surfaces |26 and |28, is caused to rotate initially and engage the pin within recesses 52. During this action the legs G4 and 66 ride on their undersurfaces along faces |24 and |22, respectively, Thereafter, member 24 rides on flat surfaces |34 and |36 formed on the lugs 45 and 48 thereof adjacent their rear ends. The members 28 and 24 are moved forwardly by the king pin until the block 54 is engaged by the forward face 56 of member 20 and compressed between said face and said front wall 58 of the housing, whereupon the legs 64 and B slide off the top surfaces |24 and |22 on the top sides of the wall portions 42 and 44 of member 24 and engage at their front ends the rear faces of said wall portions 42 and 44. It will be noted that the springs 86 and 88 constantly bias the legs 64 and 66 downwardly so that there is no possibility of the coupler members rebounding rearwardly with the king pin before the forward ends of legs 64 and 66 engage behind the walls 42 and 44 of member 24, thus preventing accidental uncoupling between the tractor and the trailer.

It will be noted that in the locked position of unit 62 the rear end of the cam member |06 is engageable as at |48 with an abutment surface |42 at the forward side of leg 12.

To uncouple, the cam member is again rotated to lockset the legs and the procedure repeated as hereinbefore set forth.

Referring now to Figures 7 to 9, it will be noted that the arrangement is similar to that heretofore described and corresponding parts are indicated by corresponding reference numerals. In the present embodiment the tension spring is eliminated and the locking member, generally designated 200, comprises spaced legs 202 and 204 connected at the axis of rotation of the member 200 to depending legs 206 and 208, respectively, said legs 206 and 208 being interconnected by a transverse member or bar 2|0. Each leg 202 and 204 is provided on the top side thereof with a pocket 2|2 affording a spring seat as at 2|4 for the lower end of a compression spring 2| 6. Each pocket 2|2 is provided with upwardly diverging sides 2|8 and 220 forwardly and rearwardly of the associated spring 2 I6 to prevent binding. Each spring 2|6 seats at its upper end as at 222 against the underside of the plate 4 and is positioned by a surrounding, depending boss 224 on the plate 4. The boss 2|6 comprises downwardly diverging surfaces forwardly and rearwardly of the spring.

The operation of the locking member 200 is the same as in the previous embodiment and is raised to lockset position as shown in Figure 8 by means of the cam |06 which locks behind the shoulder |20. The coupler is opened by moving the coupler rearwardly whereupon the surfaces |22 and |24 on rear jaw 24 are caused to engage the undersurfaces of the legs 204 and 202, causing the locking member 200 to rotate upwardly in a clockwise direction (Figure 7) or counterclockwise direction (Figure 8) to disengage the cam |06 from the shoulder |20 whereupon the cam is permitted to rotate in a clockwise direction (Figure 8). As in the previous embodiment, the rear end |40 of the cam member is engageable with an abutment surface |42 on the leg 206 of the locking member when the locking member 200 is in locked position, as shown in Figure 7, with the coupler |2.

It will be understood that in each embodiment the sides of the spring pockets adjacent to and remote from the axis of rotation of the locking member are arranged in such a manner that in locked position of the locking member the sides adjacent to the axis extend substantially parallel to the axis of the associated spring and in locked position of the locking member the faces of the pockets remote from the axis of rotation of the locking member are substantially parallel to the axis of the spring.

The dual spring arrangement at opposite sides of the locking member tends to equalize wear at the pivot points and tends to balance the locking member against transaxial rotation.

I claim:

1. In a fifth wheel coupling arrangement, the combination of a fifth wheel structure, forward and rear jaws pivoted to each other and slidably supported by said structure for fore and aft movement relative thereto, said structure having guide means for pivoting the rear jaw upwardly to closed position as the jaws slide forwardly and for accommodating pivotal movement of the rear jaw downwardly to open position as the jaws slide rearwardly, a lock comprising a pair of spaced forwardly projecting locking legs spaced approximately equidistantly from the longitudinal vertical center plane of said structure, a pair of legs depending from respective locking legs, said depending legs being interconnected by a crosspiece, said lock having hubs at the juncture of said locking legs with said depending legs, pivot means pivotally connecting said hubs to said structure on a substantially horizontal axis whereby the lock pivots upwardly on said axis to unlocked position and pivots downwardly on said axis to locked position whereat said locking legs abut rearwardly facing surfaces of said rear jaw, a tension spring connected at one end thereof to the depending leg at one side of said plane, said spring extending rearwardly from said leg and said spring being connected at its other end to said structure, the longitudinal axis of said spring being dened by a vertical plane approximately parallel to said center plane, a compression spring compressed between the structure and an upwardly facing surface of the locking leg at the opposite side of said plane, said compression spring having its compressional axis dened by a vertical plane approximately parallel to said center plane, whereby said springs are disposed at opposite sides of said center plane approximately equidistantly therefrom to bias the lock to locked position, and whereby forces of said springs tend to prevent torsion in said pivot means.

2. In a coupling arrangement, a fifth wheel including a top plate having a downwardly-facing spring seat and a rearwardly opening slot, a coupler carried by said wheel beneath said plate, locking means for said coupler comprising an element pivoted to the plate for rotation on an axis to locking position and unlocking position with respect to said coupler, a pocket on said element. and means for constantly urging said element to the locking position thereof comprising a coil spring compressed between said element and said plate on a compressional axis substantially perpendicular to the rotational axis of said element, said pocket having a substantially round bottom complementary to and affording a seat for one end of the spring and said pocket having an oval shaped portion with mutually facing sides diverging from said seat to the open end of said pocket, the opposite end of said spring being engaged with the first mentioned seat, said seats converging rearwardly with respect to each other when the lock is in locked position and said seats converging forwardly with respect to each other wh-en the lock is in unlocked position, said sides being formed and arranged to accommodate free compression and decompression of said spring at all times during rotation of the element on said rotational axis, one of said sides of said pocket facing said rotational axis and being substantially parallel to said compressional axis when the element is in unlocking position and the other of said sides of said pocket being substantially parallel to said compressional axis when the element is in locking position, whereby the compressional axis of said spring is substantially straight at all times to substantially avoid bending stresses on the spring.

FRANK H. KAYLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,015,313 Kinne Sept. 24, 1935 2,035,486 Larson Mar. 31, 1986 2,125,611 Hennicke Aug. 2, 1938 2,431,779 Stevins Dec. 2, 1947 

